PROJECT SUMMARY/ABSTRACT This multidisciplinary five-year program provides integrated training in Environmental Biostatistics, Environmental Epidemiology, and Environmental Health Science, with the goal of preparing scientists to address emerging challenges in modern environmental health research. By constructing a training program that involves collaboration across three critical scientific areas, we have a unique opportunity to advance environmental health in ways that could not be achieved if the training were conducted via three separate programs. Funding is requested for 23 predoctoral (9 BIOS, 7 EPID, 7 ENVR) and 5 postdoctoral trainees (1 BIOS, 2 EPID, 2 ENVR). Assessment of exposure-disease relationships requires understanding connections between exposure, early biological effects, host-factors, and potential interactions with the environment. Thus current environmental health research, whether involving experiments with laboratory animals or observational studies of human populations, is becoming increasingly complex. Across the lifespan, individuals are exposed to multiple contaminants at varying windows of development. These windows may differ in their sensitivities to toxic insults, potentially resulting in different health outcomes. Understanding the relationship between environmental toxicants and disease susceptibility therefore requires sophistication in the measurement of biological markers of exposure and disease processes. New technologies that allow investigators to obtain a more comprehensive estimate of exposure (the exposome), in combination with `omics- scale biological markers (genomes, epigenomes, microbiomes, proteomes and metabolomes) present both opportunities and challenges to the next generation of environmental science researchers. The ability to incorporate these data into a sophisticated systems biological framework is essential and requires cross-disciplinary training in exposure science, epidemiology, and biostatistics. A program that prepares and trains students to integrate these next-generation tools in the ?big data? era is essential to environmental health science research.